There's no mystery here: Ashley Park is joining the cast of Only Murders in the Building.

The James CaldwellEmily in Paris actress announced the news on Feb. 22 with a hilarious TikTok of her alongside co-stars Selena Gomez and Martin Short, where the three of them are seen lip-syncing to a dialogue from 1942 film My Sister Eileen.

"murders?? IN THIS BUILDING????" Ashley captioned the video. "So excited to join this killer (pun intended) cast of amazing humans."

Ashley is set to play Kimber, a Broadway star, according to Deadline.

The 31-year-old also reposted the TikTok to her Instagram Story, adding, "Shenanigans with sweetest @selenagomez and magic Martin Short…been having the best time on this set. beyond excited to be joining @onlymurdershulu and their wildly cool cast this season!!"

Who else makes up season three's star-studded cast? The upcoming season will see Selena, Martin and Steve Martin join by Meryl Streep and Paul Rudd, whose cast announcement was shared on social media in January.

"Hey guys, we're on set," Selena said in an Instagram clip posted Jan. 17. "What are we shooting?"

As Martin and Steve appeared on video, Selena added, "Season three, the gang is back. Could this honestly get any better?"

And that's when Paul appeared, noting, "Well, I do think it could get a little bit better." 

How so? Well, fans got their answer when Meryl popped up from behind a couch. Selena captioned the video, "I could cry, season 3 is coming!"

And we could cry, too, with this dream cast line-up.

The first two season of Only Murders In The Building are available to stream on Hulu.

For the latest breaking news updates, click here to download the E! News App